1. Field of Invention
This invention relates generally to the field of latch spring assemblies for the retention of a plurality of assembled structural elements and more particularly to spring wire latch assemblies for the retention of guide pin received in a disc brake caliper for guiding and supporting an opposed pair of disc brake pad members which support opposed friction pads for engagement of opposite peripheral sides or faces of a vehicle brake disc.
2. Description of the Prior Art
In conventional disc brake assemblies which incorporate disc brake calipers to the floating type in vehicle braking systems, the floating caliper, which is mounted stationary with respect to the vehicle, straddles a braking disc periphery which rotates with the vehicle wheel. A pair of disc brake pad members, which consist of backup plates with attached brake friction pads that respectively face each other on opposite peripheral side faces of the brake disc for respective frictional braking engagement, are retained between opposed caliper walls of the caliper body by means of a pair of spaced guide pins which pass transversely through the pad members. One or both of the brake pad members are thus permitted to slide toward each other on the guide pins for frictional engagement with the peripheral sides of the brake discs and to slide away from each other for disengagement of the brakes. Generally, either one or both of the pad members are permitted to freely slide on the guide pins depending respectively whether only one of the pad members is to be engaged and moved by a brake piston or both pad members are so engaged and simultaneously moved for braking engagement with the disc by respective brake pistons.
These guide pins generally pass through opposed walls of the caliper body at the end portion of the pin and one end of each guide pin is provided with an enlarged pin head to engage the outside of the caliper body in order to prevent the pin from sliding clear through the respective retention hole in the caliper body. These guide pins are then retained in their assembled position to prevent accidental dislodgement by means of one or two latch springs (usually formed of stainless steel or steel spring wire) which diametrically pass through openings or in recesses in the pins.
However, these latch spring assemblies of the prior art are deficient in that some of the latch springs are difficult to position in assembled form, others rely strictly on the provision of a guide pin head at the end of each guide pin to assist in maintaining the guide pin assembly, still other single latch spring assemblies, wherein one latch spring is utilized to retain both guide pins, are such that if one leg of the latch spring breaks, both guide pins may be dislodged due to wheel vibration and applied braking friction, or yet still others are such that the latching pin or pins are engaged with or adjacent the backup plates of the two friction pad members such that retention of the guide pins is endangered by or associated with wear or excessive wear of the friction pads.
It is the principal object of the present invention to eliminate these deficiencies of the prior art floating disc brake assemblies while simultaneously providing an assembly which is more economically manufactured and more readily assembled and disassembled.